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<pre><span class="sourceLineNo">001</span><a name="line.1"></a>
<span class="sourceLineNo">002</span>/*<a name="line.2"></a>
<span class="sourceLineNo">003</span> * Copyright (C) 2014 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<span class="sourceLineNo">004</span> *<a name="line.4"></a>
<span class="sourceLineNo">005</span> * $Id: SimpleKVDatabase.html 939 2015-05-29 01:16:17Z archie.cobbs $<a name="line.5"></a>
<span class="sourceLineNo">006</span> */<a name="line.6"></a>
<span class="sourceLineNo">007</span><a name="line.7"></a>
<span class="sourceLineNo">008</span>package org.jsimpledb.kv.simple;<a name="line.8"></a>
<span class="sourceLineNo">009</span><a name="line.9"></a>
<span class="sourceLineNo">010</span>import java.util.Arrays;<a name="line.10"></a>
<span class="sourceLineNo">011</span>import java.util.NoSuchElementException;<a name="line.11"></a>
<span class="sourceLineNo">012</span>import java.util.SortedSet;<a name="line.12"></a>
<span class="sourceLineNo">013</span><a name="line.13"></a>
<span class="sourceLineNo">014</span>import org.jsimpledb.kv.KVDatabase;<a name="line.14"></a>
<span class="sourceLineNo">015</span>import org.jsimpledb.kv.KVPair;<a name="line.15"></a>
<span class="sourceLineNo">016</span>import org.jsimpledb.kv.KVStore;<a name="line.16"></a>
<span class="sourceLineNo">017</span>import org.jsimpledb.kv.KeyRange;<a name="line.17"></a>
<span class="sourceLineNo">018</span>import org.jsimpledb.kv.RetryTransactionException;<a name="line.18"></a>
<span class="sourceLineNo">019</span>import org.jsimpledb.kv.StaleTransactionException;<a name="line.19"></a>
<span class="sourceLineNo">020</span>import org.jsimpledb.kv.TransactionTimeoutException;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import org.jsimpledb.kv.mvcc.LockManager;<a name="line.21"></a>
<span class="sourceLineNo">022</span>import org.jsimpledb.kv.util.NavigableMapKVStore;<a name="line.22"></a>
<span class="sourceLineNo">023</span>import org.jsimpledb.util.ByteUtil;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import org.slf4j.Logger;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import org.slf4j.LoggerFactory;<a name="line.25"></a>
<span class="sourceLineNo">026</span><a name="line.26"></a>
<span class="sourceLineNo">027</span>/**<a name="line.27"></a>
<span class="sourceLineNo">028</span> * Simple implementation of the {@link KVDatabase} interface that provides a concurrent, transactional view<a name="line.28"></a>
<span class="sourceLineNo">029</span> * of an underlying {@link KVStore} with strong ACID semantics (&lt;b&gt;D&lt;/b&gt;urability must be provided by the {@link KVStore}).<a name="line.29"></a>
<span class="sourceLineNo">030</span> *<a name="line.30"></a>
<span class="sourceLineNo">031</span> * &lt;p&gt;<a name="line.31"></a>
<span class="sourceLineNo">032</span> * The ACID semantics, as well as {@linkplain #getWaitTimeout wait timeouts} and {@linkplain #getHoldTimeout hold timeouts},<a name="line.32"></a>
<span class="sourceLineNo">033</span> * are provided by the {@link LockManager} class. If the wait timeout is exceeded, a {@link RetryTransactionException}<a name="line.33"></a>
<span class="sourceLineNo">034</span> * is thrown. If the hold timeout is exceeded, a {@link TransactionTimeoutException} is thrown.<a name="line.34"></a>
<span class="sourceLineNo">035</span> * &lt;/p&gt;<a name="line.35"></a>
<span class="sourceLineNo">036</span> *<a name="line.36"></a>
<span class="sourceLineNo">037</span> * &lt;p&gt;<a name="line.37"></a>
<span class="sourceLineNo">038</span> * Instances wrap an underlying {@link KVStore} which provides persistence and from which committed data is read and written.<a name="line.38"></a>
<span class="sourceLineNo">039</span> * During a transaction, all mutations are recorded internally; if/when the transaction is committed, those mutations are<a name="line.39"></a>
<span class="sourceLineNo">040</span> * applied to the underlying {@link KVStore} all at once, and this operation is bracketed by calls to<a name="line.40"></a>
<span class="sourceLineNo">041</span> * {@link #preCommit preCommit()} and {@link #postCommit postCommit()}.<a name="line.41"></a>
<span class="sourceLineNo">042</span> * &lt;/p&gt;<a name="line.42"></a>
<span class="sourceLineNo">043</span> *<a name="line.43"></a>
<span class="sourceLineNo">044</span> * @see LockManager<a name="line.44"></a>
<span class="sourceLineNo">045</span> */<a name="line.45"></a>
<span class="sourceLineNo">046</span>public class SimpleKVDatabase implements KVDatabase {<a name="line.46"></a>
<span class="sourceLineNo">047</span><a name="line.47"></a>
<span class="sourceLineNo">048</span>    /**<a name="line.48"></a>
<span class="sourceLineNo">049</span>     * Default {@linkplain #getWaitTimeout wait timeout} for newly created transactions in milliseconds<a name="line.49"></a>
<span class="sourceLineNo">050</span>     * ({@value DEFAULT_WAIT_TIMEOUT}).<a name="line.50"></a>
<span class="sourceLineNo">051</span>     */<a name="line.51"></a>
<span class="sourceLineNo">052</span>    public static final long DEFAULT_WAIT_TIMEOUT = 500;<a name="line.52"></a>
<span class="sourceLineNo">053</span><a name="line.53"></a>
<span class="sourceLineNo">054</span>    /**<a name="line.54"></a>
<span class="sourceLineNo">055</span>     * Default {@linkplain #getHoldTimeout hold timeout} in milliseconds ({@value DEFAULT_HOLD_TIMEOUT}).<a name="line.55"></a>
<span class="sourceLineNo">056</span>     */<a name="line.56"></a>
<span class="sourceLineNo">057</span>    public static final long DEFAULT_HOLD_TIMEOUT = 5000;<a name="line.57"></a>
<span class="sourceLineNo">058</span><a name="line.58"></a>
<span class="sourceLineNo">059</span>    /**<a name="line.59"></a>
<span class="sourceLineNo">060</span>     * The {@link KVStore} for the committed data.<a name="line.60"></a>
<span class="sourceLineNo">061</span>     */<a name="line.61"></a>
<span class="sourceLineNo">062</span>    protected final KVStore kv;<a name="line.62"></a>
<span class="sourceLineNo">063</span><a name="line.63"></a>
<span class="sourceLineNo">064</span>    protected final Logger log = LoggerFactory.getLogger(this.getClass());<a name="line.64"></a>
<span class="sourceLineNo">065</span><a name="line.65"></a>
<span class="sourceLineNo">066</span>    private final LockManager lockManager = new LockManager(this);<a name="line.66"></a>
<span class="sourceLineNo">067</span><a name="line.67"></a>
<span class="sourceLineNo">068</span>    private long waitTimeout;<a name="line.68"></a>
<span class="sourceLineNo">069</span><a name="line.69"></a>
<span class="sourceLineNo">070</span>    /**<a name="line.70"></a>
<span class="sourceLineNo">071</span>     * Constructor. Uses an internal in-memory {@link KVStore} and the default wait and hold timeouts.<a name="line.71"></a>
<span class="sourceLineNo">072</span>     */<a name="line.72"></a>
<span class="sourceLineNo">073</span>    public SimpleKVDatabase() {<a name="line.73"></a>
<span class="sourceLineNo">074</span>        this(new NavigableMapKVStore());<a name="line.74"></a>
<span class="sourceLineNo">075</span>    }<a name="line.75"></a>
<span class="sourceLineNo">076</span><a name="line.76"></a>
<span class="sourceLineNo">077</span>    /**<a name="line.77"></a>
<span class="sourceLineNo">078</span>     * Constructor taking caller-supplied storage. Will use the default wait and hold timeouts.<a name="line.78"></a>
<span class="sourceLineNo">079</span>     *<a name="line.79"></a>
<span class="sourceLineNo">080</span>     * @param kv {@link KVStore} for the committed data, or null for an in-memory {@link KVStore}<a name="line.80"></a>
<span class="sourceLineNo">081</span>     */<a name="line.81"></a>
<span class="sourceLineNo">082</span>    public SimpleKVDatabase(KVStore kv) {<a name="line.82"></a>
<span class="sourceLineNo">083</span>        this(kv, DEFAULT_WAIT_TIMEOUT, DEFAULT_HOLD_TIMEOUT);<a name="line.83"></a>
<span class="sourceLineNo">084</span>    }<a name="line.84"></a>
<span class="sourceLineNo">085</span><a name="line.85"></a>
<span class="sourceLineNo">086</span>    /**<a name="line.86"></a>
<span class="sourceLineNo">087</span>     * Constructor taking timeout settings. Uses an internal in-memory {@link KVStore}.<a name="line.87"></a>
<span class="sourceLineNo">088</span>     *<a name="line.88"></a>
<span class="sourceLineNo">089</span>     * @param waitTimeout how long a thread will wait for a lock before throwing {@link RetryTransactionException}<a name="line.89"></a>
<span class="sourceLineNo">090</span>     *  in milliseconds, or zero for unlimited<a name="line.90"></a>
<span class="sourceLineNo">091</span>     * @param holdTimeout how long a thread may hold a contestested lock before throwing {@link RetryTransactionException}<a name="line.91"></a>
<span class="sourceLineNo">092</span>     *  in milliseconds, or zero for unlimited<a name="line.92"></a>
<span class="sourceLineNo">093</span>     * @throws IllegalArgumentException if {@code waitTimeout} or {@code holdTimeout} is negative<a name="line.93"></a>
<span class="sourceLineNo">094</span>     */<a name="line.94"></a>
<span class="sourceLineNo">095</span>    public SimpleKVDatabase(long waitTimeout, long holdTimeout) {<a name="line.95"></a>
<span class="sourceLineNo">096</span>        this(null, waitTimeout, holdTimeout);<a name="line.96"></a>
<span class="sourceLineNo">097</span>    }<a name="line.97"></a>
<span class="sourceLineNo">098</span><a name="line.98"></a>
<span class="sourceLineNo">099</span>    /**<a name="line.99"></a>
<span class="sourceLineNo">100</span>     * Primary constructor.<a name="line.100"></a>
<span class="sourceLineNo">101</span>     *<a name="line.101"></a>
<span class="sourceLineNo">102</span>     * @param kv {@link KVStore} for the committed data, or null for an in-memory {@link KVStore}<a name="line.102"></a>
<span class="sourceLineNo">103</span>     * @param waitTimeout how long a thread will wait for a lock before throwing {@link RetryTransactionException}<a name="line.103"></a>
<span class="sourceLineNo">104</span>     *  in milliseconds, or zero for unlimited<a name="line.104"></a>
<span class="sourceLineNo">105</span>     * @param holdTimeout how long a thread may hold a contestested lock before throwing {@link RetryTransactionException}<a name="line.105"></a>
<span class="sourceLineNo">106</span>     *  in milliseconds, or zero for unlimited<a name="line.106"></a>
<span class="sourceLineNo">107</span>     * @throws IllegalArgumentException if {@code waitTimeout} or {@code holdTimeout} is negative<a name="line.107"></a>
<span class="sourceLineNo">108</span>     */<a name="line.108"></a>
<span class="sourceLineNo">109</span>    public SimpleKVDatabase(KVStore kv, long waitTimeout, long holdTimeout) {<a name="line.109"></a>
<span class="sourceLineNo">110</span>        this.kv = kv != null ? kv : new NavigableMapKVStore();<a name="line.110"></a>
<span class="sourceLineNo">111</span>        this.setWaitTimeout(waitTimeout);<a name="line.111"></a>
<span class="sourceLineNo">112</span>        this.setHoldTimeout(holdTimeout);<a name="line.112"></a>
<span class="sourceLineNo">113</span>    }<a name="line.113"></a>
<span class="sourceLineNo">114</span><a name="line.114"></a>
<span class="sourceLineNo">115</span>    /**<a name="line.115"></a>
<span class="sourceLineNo">116</span>     * Get the wait timeout for newly created transactions.<a name="line.116"></a>
<span class="sourceLineNo">117</span>     *<a name="line.117"></a>
<span class="sourceLineNo">118</span>     * &lt;p&gt;<a name="line.118"></a>
<span class="sourceLineNo">119</span>     * The wait timeout limits how long a thread will wait for a contested lock before giving up and throwing<a name="line.119"></a>
<span class="sourceLineNo">120</span>     * {@link RetryTransactionException}.<a name="line.120"></a>
<span class="sourceLineNo">121</span>     * &lt;/p&gt;<a name="line.121"></a>
<span class="sourceLineNo">122</span>     *<a name="line.122"></a>
<span class="sourceLineNo">123</span>     * @return wait timeout in milliseconds<a name="line.123"></a>
<span class="sourceLineNo">124</span>     */<a name="line.124"></a>
<span class="sourceLineNo">125</span>    public synchronized long getWaitTimeout() {<a name="line.125"></a>
<span class="sourceLineNo">126</span>        return this.waitTimeout;<a name="line.126"></a>
<span class="sourceLineNo">127</span>    }<a name="line.127"></a>
<span class="sourceLineNo">128</span><a name="line.128"></a>
<span class="sourceLineNo">129</span>    /**<a name="line.129"></a>
<span class="sourceLineNo">130</span>     * Set the wait timeout for newly created transactions. Default is {@link #DEFAULT_WAIT_TIMEOUT}.<a name="line.130"></a>
<span class="sourceLineNo">131</span>     *<a name="line.131"></a>
<span class="sourceLineNo">132</span>     * @param waitTimeout how long a thread will wait for a lock before throwing {@link RetryTransactionException}<a name="line.132"></a>
<span class="sourceLineNo">133</span>     *  in milliseconds (default), or zero for unlimited<a name="line.133"></a>
<span class="sourceLineNo">134</span>     * @throws IllegalArgumentException if {@code waitTimeout} is negative<a name="line.134"></a>
<span class="sourceLineNo">135</span>     */<a name="line.135"></a>
<span class="sourceLineNo">136</span>    public synchronized void setWaitTimeout(long waitTimeout) {<a name="line.136"></a>
<span class="sourceLineNo">137</span>        if (waitTimeout &lt; 0)<a name="line.137"></a>
<span class="sourceLineNo">138</span>            throw new IllegalArgumentException("waitTimeout &lt; 0");<a name="line.138"></a>
<span class="sourceLineNo">139</span>        this.waitTimeout = waitTimeout;<a name="line.139"></a>
<span class="sourceLineNo">140</span>    }<a name="line.140"></a>
<span class="sourceLineNo">141</span><a name="line.141"></a>
<span class="sourceLineNo">142</span>    /**<a name="line.142"></a>
<span class="sourceLineNo">143</span>     * Get the hold timeout configured for this instance.<a name="line.143"></a>
<span class="sourceLineNo">144</span>     *<a name="line.144"></a>
<span class="sourceLineNo">145</span>     * &lt;p&gt;<a name="line.145"></a>
<span class="sourceLineNo">146</span>     * The hold timeout limits how long a thread may hold on to a contested lock before being forced to release<a name="line.146"></a>
<span class="sourceLineNo">147</span>     * all of its locks; after that, the next attempted operation will fail with {@link RetryTransactionException}.<a name="line.147"></a>
<span class="sourceLineNo">148</span>     * &lt;/p&gt;<a name="line.148"></a>
<span class="sourceLineNo">149</span>     *<a name="line.149"></a>
<span class="sourceLineNo">150</span>     * @return hold timeout in milliseconds<a name="line.150"></a>
<span class="sourceLineNo">151</span>     */<a name="line.151"></a>
<span class="sourceLineNo">152</span>    public long getHoldTimeout() {<a name="line.152"></a>
<span class="sourceLineNo">153</span>        return this.lockManager.getHoldTimeout();<a name="line.153"></a>
<span class="sourceLineNo">154</span>    }<a name="line.154"></a>
<span class="sourceLineNo">155</span><a name="line.155"></a>
<span class="sourceLineNo">156</span>    /**<a name="line.156"></a>
<span class="sourceLineNo">157</span>     * Set the hold timeout for this instance. Default is {@link #DEFAULT_HOLD_TIMEOUT}.<a name="line.157"></a>
<span class="sourceLineNo">158</span>     *<a name="line.158"></a>
<span class="sourceLineNo">159</span>     * @param holdTimeout how long a thread may hold a contestested lock before throwing {@link RetryTransactionException}<a name="line.159"></a>
<span class="sourceLineNo">160</span>     *  in milliseconds, or zero for unlimited<a name="line.160"></a>
<span class="sourceLineNo">161</span>     * @throws IllegalArgumentException if {@code holdTimeout} is negative<a name="line.161"></a>
<span class="sourceLineNo">162</span>     */<a name="line.162"></a>
<span class="sourceLineNo">163</span>    public void setHoldTimeout(long holdTimeout) {<a name="line.163"></a>
<span class="sourceLineNo">164</span>        this.lockManager.setHoldTimeout(holdTimeout);<a name="line.164"></a>
<span class="sourceLineNo">165</span>    }<a name="line.165"></a>
<span class="sourceLineNo">166</span><a name="line.166"></a>
<span class="sourceLineNo">167</span>    @Override<a name="line.167"></a>
<span class="sourceLineNo">168</span>    public synchronized SimpleKVTransaction createTransaction() {<a name="line.168"></a>
<span class="sourceLineNo">169</span>        return new SimpleKVTransaction(this, this.waitTimeout);<a name="line.169"></a>
<span class="sourceLineNo">170</span>    }<a name="line.170"></a>
<span class="sourceLineNo">171</span><a name="line.171"></a>
<span class="sourceLineNo">172</span>// Subclass hooks<a name="line.172"></a>
<span class="sourceLineNo">173</span><a name="line.173"></a>
<span class="sourceLineNo">174</span>    /**<a name="line.174"></a>
<span class="sourceLineNo">175</span>     * Invoked during transaction commit just prior to writing changes to the underlying {@link KVStore}.<a name="line.175"></a>
<span class="sourceLineNo">176</span>     *<a name="line.176"></a>
<span class="sourceLineNo">177</span>     * &lt;p&gt;<a name="line.177"></a>
<span class="sourceLineNo">178</span>     * {@link SimpleKVDatabase} guarantees this method and {@link #postCommit postCommit()} will be invoked in matching pairs,<a name="line.178"></a>
<span class="sourceLineNo">179</span>     * and that this instance will be locked when these methods are invoked.<a name="line.179"></a>
<span class="sourceLineNo">180</span>     * &lt;/p&gt;<a name="line.180"></a>
<span class="sourceLineNo">181</span>     *<a name="line.181"></a>
<span class="sourceLineNo">182</span>     * &lt;p&gt;<a name="line.182"></a>
<span class="sourceLineNo">183</span>     * The implementation in {@link SimpleKVDatabase} does nothing.<a name="line.183"></a>
<span class="sourceLineNo">184</span>     * &lt;/p&gt;<a name="line.184"></a>
<span class="sourceLineNo">185</span>     *<a name="line.185"></a>
<span class="sourceLineNo">186</span>     * @param tx the transaction about to be committed<a name="line.186"></a>
<span class="sourceLineNo">187</span>     * @throws RetryTransactionException if this transaction must be retried and is no longer usable<a name="line.187"></a>
<span class="sourceLineNo">188</span>     */<a name="line.188"></a>
<span class="sourceLineNo">189</span>    protected void preCommit(SimpleKVTransaction tx) {<a name="line.189"></a>
<span class="sourceLineNo">190</span>    }<a name="line.190"></a>
<span class="sourceLineNo">191</span><a name="line.191"></a>
<span class="sourceLineNo">192</span>    /**<a name="line.192"></a>
<span class="sourceLineNo">193</span>     * Invoked during transaction commit just after writing changes to the underlying {@link KVStore}.<a name="line.193"></a>
<span class="sourceLineNo">194</span>     *<a name="line.194"></a>
<span class="sourceLineNo">195</span>     * &lt;p&gt;<a name="line.195"></a>
<span class="sourceLineNo">196</span>     * {@link SimpleKVDatabase} guarantees this method and {@link #preCommit preCommit()} will be invoked in matching pairs,<a name="line.196"></a>
<span class="sourceLineNo">197</span>     * and that this instance will be locked when these methods are invoked.<a name="line.197"></a>
<span class="sourceLineNo">198</span>     * &lt;/p&gt;<a name="line.198"></a>
<span class="sourceLineNo">199</span>     *<a name="line.199"></a>
<span class="sourceLineNo">200</span>     * &lt;p&gt;<a name="line.200"></a>
<span class="sourceLineNo">201</span>     * This method is invoked even if the underlying {@link KVStore} throws an exception while changes were being written to it.<a name="line.201"></a>
<span class="sourceLineNo">202</span>     * In that case, {@code successful} will be false.<a name="line.202"></a>
<span class="sourceLineNo">203</span>     * &lt;/p&gt;<a name="line.203"></a>
<span class="sourceLineNo">204</span>     *<a name="line.204"></a>
<span class="sourceLineNo">205</span>     * &lt;p&gt;<a name="line.205"></a>
<span class="sourceLineNo">206</span>     * The implementation in {@link SimpleKVDatabase} does nothing.<a name="line.206"></a>
<span class="sourceLineNo">207</span>     * &lt;/p&gt;<a name="line.207"></a>
<span class="sourceLineNo">208</span>     *<a name="line.208"></a>
<span class="sourceLineNo">209</span>     * @param tx the transaction that was committed<a name="line.209"></a>
<span class="sourceLineNo">210</span>     * @param successful true if all changes were written back successfully,<a name="line.210"></a>
<span class="sourceLineNo">211</span>     *  false if the underlying {@link KVStore} threw an exception during commit update<a name="line.211"></a>
<span class="sourceLineNo">212</span>     */<a name="line.212"></a>
<span class="sourceLineNo">213</span>    protected void postCommit(SimpleKVTransaction tx, boolean successful) {<a name="line.213"></a>
<span class="sourceLineNo">214</span>    }<a name="line.214"></a>
<span class="sourceLineNo">215</span><a name="line.215"></a>
<span class="sourceLineNo">216</span>    /**<a name="line.216"></a>
<span class="sourceLineNo">217</span>     * Verify that the given transaction is still usable.<a name="line.217"></a>
<span class="sourceLineNo">218</span>     *<a name="line.218"></a>
<span class="sourceLineNo">219</span>     * &lt;p&gt;<a name="line.219"></a>
<span class="sourceLineNo">220</span>     * This method is invoked at the start of the {@link KVStore} data access and {@link SimpleKVTransaction#commit commit()}<a name="line.220"></a>
<span class="sourceLineNo">221</span>     * methods of the {@link SimpleKVTransaction} associated with this instance. This allows for any checks which depend on<a name="line.221"></a>
<span class="sourceLineNo">222</span>     * a consistent view of the transaction and database together. This instance's lock will be held when this method is invoked.<a name="line.222"></a>
<span class="sourceLineNo">223</span>     * Note: transaction state is also protected by this instance's lock.<a name="line.223"></a>
<span class="sourceLineNo">224</span>     * &lt;/p&gt;<a name="line.224"></a>
<span class="sourceLineNo">225</span>     *<a name="line.225"></a>
<span class="sourceLineNo">226</span>     * &lt;p&gt;<a name="line.226"></a>
<span class="sourceLineNo">227</span>     * The implementation in {@link SimpleKVDatabase} does nothing.<a name="line.227"></a>
<span class="sourceLineNo">228</span>     * &lt;/p&gt;<a name="line.228"></a>
<span class="sourceLineNo">229</span>     *<a name="line.229"></a>
<span class="sourceLineNo">230</span>     * @param tx the transaction being accessed<a name="line.230"></a>
<span class="sourceLineNo">231</span>     * @throws StaleTransactionException if this instance is no longer usable<a name="line.231"></a>
<span class="sourceLineNo">232</span>     * @throws RetryTransactionException if this transaction should be retried<a name="line.232"></a>
<span class="sourceLineNo">233</span>     * @throws TransactionTimeoutException if the transaction has timed out<a name="line.233"></a>
<span class="sourceLineNo">234</span>     */<a name="line.234"></a>
<span class="sourceLineNo">235</span>    protected void checkState(SimpleKVTransaction tx) {<a name="line.235"></a>
<span class="sourceLineNo">236</span>    }<a name="line.236"></a>
<span class="sourceLineNo">237</span><a name="line.237"></a>
<span class="sourceLineNo">238</span>    private void checkUsable(SimpleKVTransaction tx) {<a name="line.238"></a>
<span class="sourceLineNo">239</span>        if (tx.stale)<a name="line.239"></a>
<span class="sourceLineNo">240</span>            throw new StaleTransactionException(tx);<a name="line.240"></a>
<span class="sourceLineNo">241</span>        if (this.lockManager.checkHoldTimeout(tx.lockOwner) == -1) {<a name="line.241"></a>
<span class="sourceLineNo">242</span>            this.rollback(tx);<a name="line.242"></a>
<span class="sourceLineNo">243</span>            throw new TransactionTimeoutException(tx,<a name="line.243"></a>
<span class="sourceLineNo">244</span>              "transaction taking too long: hold timeout of " + this.lockManager.getHoldTimeout() + "ms has expired");<a name="line.244"></a>
<span class="sourceLineNo">245</span>        }<a name="line.245"></a>
<span class="sourceLineNo">246</span>    }<a name="line.246"></a>
<span class="sourceLineNo">247</span><a name="line.247"></a>
<span class="sourceLineNo">248</span>// SimpleKVTransaction hooks<a name="line.248"></a>
<span class="sourceLineNo">249</span><a name="line.249"></a>
<span class="sourceLineNo">250</span>    synchronized byte[] get(SimpleKVTransaction tx, byte[] key) {<a name="line.250"></a>
<span class="sourceLineNo">251</span><a name="line.251"></a>
<span class="sourceLineNo">252</span>        // Sanity check<a name="line.252"></a>
<span class="sourceLineNo">253</span>        if (key.length &gt; 0 &amp;&amp; key[0] == (byte)0xff)<a name="line.253"></a>
<span class="sourceLineNo">254</span>            throw new IllegalArgumentException("key starts with 0xff");<a name="line.254"></a>
<span class="sourceLineNo">255</span>        this.checkUsable(tx);<a name="line.255"></a>
<span class="sourceLineNo">256</span>        this.checkState(tx);<a name="line.256"></a>
<span class="sourceLineNo">257</span><a name="line.257"></a>
<span class="sourceLineNo">258</span>        // Check transaction mutations<a name="line.258"></a>
<span class="sourceLineNo">259</span>        final Mutation mutation = tx.findMutation(key);<a name="line.259"></a>
<span class="sourceLineNo">260</span>        if (mutation != null)<a name="line.260"></a>
<span class="sourceLineNo">261</span>            return mutation instanceof Put ? ((Put)mutation).getValue() : null;<a name="line.261"></a>
<span class="sourceLineNo">262</span><a name="line.262"></a>
<span class="sourceLineNo">263</span>        // Read from underlying store<a name="line.263"></a>
<span class="sourceLineNo">264</span>        this.getLock(tx, key, ByteUtil.getNextKey(key), false);<a name="line.264"></a>
<span class="sourceLineNo">265</span>        return this.kv.get(key);<a name="line.265"></a>
<span class="sourceLineNo">266</span>    }<a name="line.266"></a>
<span class="sourceLineNo">267</span><a name="line.267"></a>
<span class="sourceLineNo">268</span>    synchronized KVPair getAtLeast(SimpleKVTransaction tx, byte[] minKey) {<a name="line.268"></a>
<span class="sourceLineNo">269</span><a name="line.269"></a>
<span class="sourceLineNo">270</span>        // Realize minKey<a name="line.270"></a>
<span class="sourceLineNo">271</span>        if (minKey == null)<a name="line.271"></a>
<span class="sourceLineNo">272</span>            minKey = ByteUtil.EMPTY;<a name="line.272"></a>
<span class="sourceLineNo">273</span><a name="line.273"></a>
<span class="sourceLineNo">274</span>        // Sanity check<a name="line.274"></a>
<span class="sourceLineNo">275</span>        this.checkUsable(tx);<a name="line.275"></a>
<span class="sourceLineNo">276</span>        this.checkState(tx);<a name="line.276"></a>
<span class="sourceLineNo">277</span><a name="line.277"></a>
<span class="sourceLineNo">278</span>        // Save original min key for locking purposes<a name="line.278"></a>
<span class="sourceLineNo">279</span>        final byte[] originalMinKey = minKey;<a name="line.279"></a>
<span class="sourceLineNo">280</span><a name="line.280"></a>
<span class="sourceLineNo">281</span>        // Look for a mutation starting before minKey but containing it<a name="line.281"></a>
<span class="sourceLineNo">282</span>        if (minKey.length &gt; 0) {<a name="line.282"></a>
<span class="sourceLineNo">283</span>            final Mutation overlap = tx.findMutation(minKey);<a name="line.283"></a>
<span class="sourceLineNo">284</span>            if (overlap != null) {<a name="line.284"></a>
<span class="sourceLineNo">285</span>                if (overlap instanceof Put) {<a name="line.285"></a>
<span class="sourceLineNo">286</span>                    final Put put = (Put)overlap;<a name="line.286"></a>
<span class="sourceLineNo">287</span>                    assert Arrays.equals(put.getKey(), minKey);<a name="line.287"></a>
<span class="sourceLineNo">288</span>                    return new KVPair(put.getKey(), put.getValue());<a name="line.288"></a>
<span class="sourceLineNo">289</span>                }<a name="line.289"></a>
<span class="sourceLineNo">290</span>                assert overlap instanceof Del;<a name="line.290"></a>
<span class="sourceLineNo">291</span>                final byte[] max = overlap.getMax();<a name="line.291"></a>
<span class="sourceLineNo">292</span>                if (max == null)<a name="line.292"></a>
<span class="sourceLineNo">293</span>                    return null;<a name="line.293"></a>
<span class="sourceLineNo">294</span>                minKey = max;<a name="line.294"></a>
<span class="sourceLineNo">295</span>            }<a name="line.295"></a>
<span class="sourceLineNo">296</span>        }<a name="line.296"></a>
<span class="sourceLineNo">297</span><a name="line.297"></a>
<span class="sourceLineNo">298</span>        // Find whichever is first: a transaction Put, or an underlying store entry not covered by a transaction Delete<a name="line.298"></a>
<span class="sourceLineNo">299</span>        SortedSet&lt;Mutation&gt; mutations = tx.mutations;<a name="line.299"></a>
<span class="sourceLineNo">300</span>        while (true) {<a name="line.300"></a>
<span class="sourceLineNo">301</span><a name="line.301"></a>
<span class="sourceLineNo">302</span>            // Get the next mutation and kvstore entry &gt;= minKey (if they exist)<a name="line.302"></a>
<span class="sourceLineNo">303</span>            if (minKey != null)<a name="line.303"></a>
<span class="sourceLineNo">304</span>                mutations = mutations.tailSet(Mutation.key(minKey));<a name="line.304"></a>
<span class="sourceLineNo">305</span>            final Mutation mutation = !mutations.isEmpty() ? mutations.first() : null;<a name="line.305"></a>
<span class="sourceLineNo">306</span>            final KVPair entry = this.kv.getAtLeast(minKey);<a name="line.306"></a>
<span class="sourceLineNo">307</span><a name="line.307"></a>
<span class="sourceLineNo">308</span>            // Handle the case where neither is found<a name="line.308"></a>
<span class="sourceLineNo">309</span>            if (mutation == null &amp;&amp; entry == null) {<a name="line.309"></a>
<span class="sourceLineNo">310</span>                this.getLock(tx, originalMinKey, null, false);<a name="line.310"></a>
<span class="sourceLineNo">311</span>                return null;<a name="line.311"></a>
<span class="sourceLineNo">312</span>            }<a name="line.312"></a>
<span class="sourceLineNo">313</span><a name="line.313"></a>
<span class="sourceLineNo">314</span>            // Check for whether mutation or kvstore wins (i.e., which is first)<a name="line.314"></a>
<span class="sourceLineNo">315</span>            if (mutation != null &amp;&amp; (entry == null || mutation.compareTo(entry.getKey()) &lt;= 0)) {<a name="line.315"></a>
<span class="sourceLineNo">316</span>                if (mutation instanceof Del) {<a name="line.316"></a>
<span class="sourceLineNo">317</span>                    if ((minKey = mutation.getMax()) == null) {<a name="line.317"></a>
<span class="sourceLineNo">318</span>                        this.getLock(tx, originalMinKey, null, false);<a name="line.318"></a>
<span class="sourceLineNo">319</span>                        return null;<a name="line.319"></a>
<span class="sourceLineNo">320</span>                    }<a name="line.320"></a>
<span class="sourceLineNo">321</span>                    continue;<a name="line.321"></a>
<span class="sourceLineNo">322</span>                }<a name="line.322"></a>
<span class="sourceLineNo">323</span>                final Put put = (Put)mutation;<a name="line.323"></a>
<span class="sourceLineNo">324</span>                this.getLock(tx, originalMinKey, ByteUtil.getNextKey(put.getKey()), false);<a name="line.324"></a>
<span class="sourceLineNo">325</span>                return new KVPair(put.getKey(), put.getValue());<a name="line.325"></a>
<span class="sourceLineNo">326</span>            } else {<a name="line.326"></a>
<span class="sourceLineNo">327</span>                this.getLock(tx, originalMinKey, ByteUtil.getNextKey(entry.getKey()), false);<a name="line.327"></a>
<span class="sourceLineNo">328</span>                return entry;<a name="line.328"></a>
<span class="sourceLineNo">329</span>            }<a name="line.329"></a>
<span class="sourceLineNo">330</span>        }<a name="line.330"></a>
<span class="sourceLineNo">331</span>    }<a name="line.331"></a>
<span class="sourceLineNo">332</span><a name="line.332"></a>
<span class="sourceLineNo">333</span>    synchronized KVPair getAtMost(SimpleKVTransaction tx, byte[] maxKey) {<a name="line.333"></a>
<span class="sourceLineNo">334</span><a name="line.334"></a>
<span class="sourceLineNo">335</span>        // Sanity check<a name="line.335"></a>
<span class="sourceLineNo">336</span>        this.checkUsable(tx);<a name="line.336"></a>
<span class="sourceLineNo">337</span>        this.checkState(tx);<a name="line.337"></a>
<span class="sourceLineNo">338</span><a name="line.338"></a>
<span class="sourceLineNo">339</span>        // Save original max key for locking purposes<a name="line.339"></a>
<span class="sourceLineNo">340</span>        final byte[] originalMaxKey = maxKey;<a name="line.340"></a>
<span class="sourceLineNo">341</span><a name="line.341"></a>
<span class="sourceLineNo">342</span>        // Find whichever is first: a transaction addition, or an underlying store entry not covered by a transaction deletion<a name="line.342"></a>
<span class="sourceLineNo">343</span>        SortedSet&lt;Mutation&gt; mutations = tx.mutations;<a name="line.343"></a>
<span class="sourceLineNo">344</span>        while (true) {<a name="line.344"></a>
<span class="sourceLineNo">345</span><a name="line.345"></a>
<span class="sourceLineNo">346</span>            // Get the next mutation and kvstore entry &lt; maxKey (if they exist)<a name="line.346"></a>
<span class="sourceLineNo">347</span>            if (maxKey != null)<a name="line.347"></a>
<span class="sourceLineNo">348</span>                mutations = mutations.headSet(Mutation.key(maxKey));<a name="line.348"></a>
<span class="sourceLineNo">349</span>            final Mutation mutation = !mutations.isEmpty() ? mutations.last() : null;<a name="line.349"></a>
<span class="sourceLineNo">350</span>            final KVPair entry = this.kv.getAtMost(maxKey);<a name="line.350"></a>
<span class="sourceLineNo">351</span><a name="line.351"></a>
<span class="sourceLineNo">352</span>            // Handle the case where neither is found<a name="line.352"></a>
<span class="sourceLineNo">353</span>            if (mutation == null &amp;&amp; entry == null) {<a name="line.353"></a>
<span class="sourceLineNo">354</span>                this.getLock(tx, ByteUtil.EMPTY, originalMaxKey, false);<a name="line.354"></a>
<span class="sourceLineNo">355</span>                return null;<a name="line.355"></a>
<span class="sourceLineNo">356</span>            }<a name="line.356"></a>
<span class="sourceLineNo">357</span><a name="line.357"></a>
<span class="sourceLineNo">358</span>            // Check for whether mutation or kvstore wins (i.e., which is first)<a name="line.358"></a>
<span class="sourceLineNo">359</span>            if (mutation != null &amp;&amp; (entry == null || mutation.compareTo(entry.getKey()) &gt;= 0)) {<a name="line.359"></a>
<span class="sourceLineNo">360</span>                if (mutation instanceof Del) {<a name="line.360"></a>
<span class="sourceLineNo">361</span>                    if ((maxKey = mutation.getMin()) == null) {<a name="line.361"></a>
<span class="sourceLineNo">362</span>                        this.getLock(tx, ByteUtil.EMPTY, originalMaxKey, false);<a name="line.362"></a>
<span class="sourceLineNo">363</span>                        return null;<a name="line.363"></a>
<span class="sourceLineNo">364</span>                    }<a name="line.364"></a>
<span class="sourceLineNo">365</span>                    continue;<a name="line.365"></a>
<span class="sourceLineNo">366</span>                }<a name="line.366"></a>
<span class="sourceLineNo">367</span>                final Put put = (Put)mutation;<a name="line.367"></a>
<span class="sourceLineNo">368</span>                this.getLock(tx, put.getKey(), originalMaxKey, false);<a name="line.368"></a>
<span class="sourceLineNo">369</span>                return new KVPair(put.getKey(), put.getValue());<a name="line.369"></a>
<span class="sourceLineNo">370</span>            } else {<a name="line.370"></a>
<span class="sourceLineNo">371</span>                this.getLock(tx, entry.getKey(), originalMaxKey, false);<a name="line.371"></a>
<span class="sourceLineNo">372</span>                return entry;<a name="line.372"></a>
<span class="sourceLineNo">373</span>            }<a name="line.373"></a>
<span class="sourceLineNo">374</span>        }<a name="line.374"></a>
<span class="sourceLineNo">375</span>    }<a name="line.375"></a>
<span class="sourceLineNo">376</span><a name="line.376"></a>
<span class="sourceLineNo">377</span>    synchronized void put(SimpleKVTransaction tx, byte[] key, byte[] value) {<a name="line.377"></a>
<span class="sourceLineNo">378</span><a name="line.378"></a>
<span class="sourceLineNo">379</span>        // Sanity check<a name="line.379"></a>
<span class="sourceLineNo">380</span>        if (value == null)<a name="line.380"></a>
<span class="sourceLineNo">381</span>            throw new NullPointerException();<a name="line.381"></a>
<span class="sourceLineNo">382</span>        if (key.length &gt; 0 &amp;&amp; key[0] == (byte)0xff)<a name="line.382"></a>
<span class="sourceLineNo">383</span>            throw new IllegalArgumentException("key starts with 0xff");<a name="line.383"></a>
<span class="sourceLineNo">384</span>        this.checkUsable(tx);<a name="line.384"></a>
<span class="sourceLineNo">385</span>        this.checkState(tx);<a name="line.385"></a>
<span class="sourceLineNo">386</span>        final byte[] keyNext = ByteUtil.getNextKey(key);<a name="line.386"></a>
<span class="sourceLineNo">387</span><a name="line.387"></a>
<span class="sourceLineNo">388</span>        // Check transaction mutations<a name="line.388"></a>
<span class="sourceLineNo">389</span>        final Mutation mutation = tx.findMutation(key);<a name="line.389"></a>
<span class="sourceLineNo">390</span>        if (mutation instanceof Put) {<a name="line.390"></a>
<span class="sourceLineNo">391</span>            assert Arrays.equals(((Put)mutation).getKey(), key);<a name="line.391"></a>
<span class="sourceLineNo">392</span><a name="line.392"></a>
<span class="sourceLineNo">393</span>            // Replace Put with new Put<a name="line.393"></a>
<span class="sourceLineNo">394</span>            tx.mutations.remove(mutation);<a name="line.394"></a>
<span class="sourceLineNo">395</span>            tx.mutations.add(new Put(key, value));<a name="line.395"></a>
<span class="sourceLineNo">396</span>        } else if (mutation instanceof Del) {<a name="line.396"></a>
<span class="sourceLineNo">397</span><a name="line.397"></a>
<span class="sourceLineNo">398</span>            // Split [Del] -&gt; [Del*, Put, Del*]  *if needed<a name="line.398"></a>
<span class="sourceLineNo">399</span>            final Del del = (Del)mutation;<a name="line.399"></a>
<span class="sourceLineNo">400</span>            final byte[] delMin = del.getMin();<a name="line.400"></a>
<span class="sourceLineNo">401</span>            final byte[] delMax = del.getMax();<a name="line.401"></a>
<span class="sourceLineNo">402</span>            tx.mutations.remove(del);<a name="line.402"></a>
<span class="sourceLineNo">403</span>            if (KeyRange.compare(delMin, key) &lt; 0)<a name="line.403"></a>
<span class="sourceLineNo">404</span>                tx.mutations.add(new Del(delMin, key));<a name="line.404"></a>
<span class="sourceLineNo">405</span>            if (KeyRange.compare(keyNext, delMax) &lt; 0)<a name="line.405"></a>
<span class="sourceLineNo">406</span>                tx.mutations.add(new Del(keyNext, delMax));<a name="line.406"></a>
<span class="sourceLineNo">407</span>            tx.mutations.add(new Put(key, value));<a name="line.407"></a>
<span class="sourceLineNo">408</span>        } else {<a name="line.408"></a>
<span class="sourceLineNo">409</span><a name="line.409"></a>
<span class="sourceLineNo">410</span>            // Add write lock and new tx mutation<a name="line.410"></a>
<span class="sourceLineNo">411</span>            this.getLock(tx, key, keyNext, true);<a name="line.411"></a>
<span class="sourceLineNo">412</span>            tx.mutations.add(new Put(key, value));<a name="line.412"></a>
<span class="sourceLineNo">413</span>        }<a name="line.413"></a>
<span class="sourceLineNo">414</span>    }<a name="line.414"></a>
<span class="sourceLineNo">415</span><a name="line.415"></a>
<span class="sourceLineNo">416</span>    synchronized void remove(SimpleKVTransaction tx, byte[] key) {<a name="line.416"></a>
<span class="sourceLineNo">417</span><a name="line.417"></a>
<span class="sourceLineNo">418</span>        // Sanity check<a name="line.418"></a>
<span class="sourceLineNo">419</span>        if (key.length &gt; 0 &amp;&amp; key[0] == (byte)0xff)<a name="line.419"></a>
<span class="sourceLineNo">420</span>            throw new IllegalArgumentException("key starts with 0xff");<a name="line.420"></a>
<span class="sourceLineNo">421</span>        this.checkUsable(tx);<a name="line.421"></a>
<span class="sourceLineNo">422</span>        this.checkState(tx);<a name="line.422"></a>
<span class="sourceLineNo">423</span>        final byte[] keyNext = ByteUtil.getNextKey(key);<a name="line.423"></a>
<span class="sourceLineNo">424</span><a name="line.424"></a>
<span class="sourceLineNo">425</span>        // Check transaction mutations<a name="line.425"></a>
<span class="sourceLineNo">426</span>        final Mutation mutation = tx.findMutation(key);<a name="line.426"></a>
<span class="sourceLineNo">427</span>        if (mutation instanceof Put) {<a name="line.427"></a>
<span class="sourceLineNo">428</span>            assert Arrays.equals(((Put)mutation).getKey(), key);<a name="line.428"></a>
<span class="sourceLineNo">429</span><a name="line.429"></a>
<span class="sourceLineNo">430</span>            // Replace Put with Del<a name="line.430"></a>
<span class="sourceLineNo">431</span>            tx.mutations.remove(mutation);<a name="line.431"></a>
<span class="sourceLineNo">432</span>            tx.mutations.add(new Del(key));<a name="line.432"></a>
<span class="sourceLineNo">433</span>        } else if (mutation == null) {<a name="line.433"></a>
<span class="sourceLineNo">434</span><a name="line.434"></a>
<span class="sourceLineNo">435</span>            // Add write lock and new tx mutation<a name="line.435"></a>
<span class="sourceLineNo">436</span>            this.getLock(tx, key, keyNext, true);<a name="line.436"></a>
<span class="sourceLineNo">437</span>            tx.mutations.add(new Del(key));<a name="line.437"></a>
<span class="sourceLineNo">438</span>        }<a name="line.438"></a>
<span class="sourceLineNo">439</span>    }<a name="line.439"></a>
<span class="sourceLineNo">440</span><a name="line.440"></a>
<span class="sourceLineNo">441</span>    synchronized void removeRange(SimpleKVTransaction tx, byte[] minKey, byte[] maxKey) {<a name="line.441"></a>
<span class="sourceLineNo">442</span><a name="line.442"></a>
<span class="sourceLineNo">443</span>        // Realize minKey<a name="line.443"></a>
<span class="sourceLineNo">444</span>        if (minKey == null)<a name="line.444"></a>
<span class="sourceLineNo">445</span>            minKey = ByteUtil.EMPTY;<a name="line.445"></a>
<span class="sourceLineNo">446</span><a name="line.446"></a>
<span class="sourceLineNo">447</span>        // Sanity check<a name="line.447"></a>
<span class="sourceLineNo">448</span>        int diff = KeyRange.compare(minKey, maxKey);<a name="line.448"></a>
<span class="sourceLineNo">449</span>        if (diff &gt; 0)<a name="line.449"></a>
<span class="sourceLineNo">450</span>            throw new IllegalArgumentException("minKey &gt; maxKey");<a name="line.450"></a>
<span class="sourceLineNo">451</span>        this.checkUsable(tx);<a name="line.451"></a>
<span class="sourceLineNo">452</span>        this.checkState(tx);<a name="line.452"></a>
<span class="sourceLineNo">453</span>        if (diff == 0)                                                          // range is empty<a name="line.453"></a>
<span class="sourceLineNo">454</span>            return;<a name="line.454"></a>
<span class="sourceLineNo">455</span>        final byte[] originalMinKey = minKey;<a name="line.455"></a>
<span class="sourceLineNo">456</span>        final byte[] originalMaxKey = maxKey;<a name="line.456"></a>
<span class="sourceLineNo">457</span><a name="line.457"></a>
<span class="sourceLineNo">458</span>        // Deal with partial overlap at the left end of the range<a name="line.458"></a>
<span class="sourceLineNo">459</span>        if (minKey.length &gt; 0) {<a name="line.459"></a>
<span class="sourceLineNo">460</span>            final Mutation leftMutation = tx.findMutation(minKey);<a name="line.460"></a>
<span class="sourceLineNo">461</span>            if (leftMutation instanceof Put) {<a name="line.461"></a>
<span class="sourceLineNo">462</span>                assert Arrays.equals(((Put)leftMutation).getKey(), minKey);<a name="line.462"></a>
<span class="sourceLineNo">463</span>                tx.mutations.remove(leftMutation);                                          // overwritten by this change<a name="line.463"></a>
<span class="sourceLineNo">464</span>            } else if (leftMutation instanceof Del) {<a name="line.464"></a>
<span class="sourceLineNo">465</span>                final Del del = (Del)leftMutation;<a name="line.465"></a>
<span class="sourceLineNo">466</span>                tx.mutations.remove(del);                                                   // will merge into this change<a name="line.466"></a>
<span class="sourceLineNo">467</span>                minKey = del.getMin();                                                      // guaranteed to be &lt;= minKey<a name="line.467"></a>
<span class="sourceLineNo">468</span>                if (KeyRange.compare(del.getMax(), maxKey) &gt; 0)                             // get higher of the two maxKeys<a name="line.468"></a>
<span class="sourceLineNo">469</span>                    maxKey = del.getMax();<a name="line.469"></a>
<span class="sourceLineNo">470</span>            }<a name="line.470"></a>
<span class="sourceLineNo">471</span>        }<a name="line.471"></a>
<span class="sourceLineNo">472</span><a name="line.472"></a>
<span class="sourceLineNo">473</span>        // Deal with partial overlap at the right end of the range<a name="line.473"></a>
<span class="sourceLineNo">474</span>        if (maxKey != null) {<a name="line.474"></a>
<span class="sourceLineNo">475</span>            Mutation rightMutation = null;<a name="line.475"></a>
<span class="sourceLineNo">476</span>            try {<a name="line.476"></a>
<span class="sourceLineNo">477</span>                rightMutation = minKey != null ?<a name="line.477"></a>
<span class="sourceLineNo">478</span>                  tx.mutations.subSet(Mutation.key(minKey), Mutation.key(maxKey)).last() :<a name="line.478"></a>
<span class="sourceLineNo">479</span>                  tx.mutations.headSet(Mutation.key(maxKey)).last();<a name="line.479"></a>
<span class="sourceLineNo">480</span>            } catch (NoSuchElementException e) {<a name="line.480"></a>
<span class="sourceLineNo">481</span>                // ignore<a name="line.481"></a>
<span class="sourceLineNo">482</span>            }<a name="line.482"></a>
<span class="sourceLineNo">483</span>            if (rightMutation instanceof Put)<a name="line.483"></a>
<span class="sourceLineNo">484</span>                tx.mutations.remove(rightMutation);                                         // overwritten by this change<a name="line.484"></a>
<span class="sourceLineNo">485</span>            else if (rightMutation instanceof Del) {<a name="line.485"></a>
<span class="sourceLineNo">486</span>                final Del del = (Del)rightMutation;<a name="line.486"></a>
<span class="sourceLineNo">487</span>                tx.mutations.remove(del);                                                   // will merge into this change<a name="line.487"></a>
<span class="sourceLineNo">488</span>                if (KeyRange.compare(del.getMax(), maxKey) &gt; 0)                             // get higher of the two maxKeys<a name="line.488"></a>
<span class="sourceLineNo">489</span>                    maxKey = del.getMax();<a name="line.489"></a>
<span class="sourceLineNo">490</span>            }<a name="line.490"></a>
<span class="sourceLineNo">491</span>        }<a name="line.491"></a>
<span class="sourceLineNo">492</span><a name="line.492"></a>
<span class="sourceLineNo">493</span>        // Remove all mutations in the middle<a name="line.493"></a>
<span class="sourceLineNo">494</span>        if (originalMinKey == null &amp;&amp; originalMaxKey == null)<a name="line.494"></a>
<span class="sourceLineNo">495</span>            tx.mutations.clear();<a name="line.495"></a>
<span class="sourceLineNo">496</span>        else if (originalMinKey == null)<a name="line.496"></a>
<span class="sourceLineNo">497</span>            tx.mutations.headSet(Mutation.key(originalMaxKey)).clear();<a name="line.497"></a>
<span class="sourceLineNo">498</span>        else if (originalMaxKey == null)<a name="line.498"></a>
<span class="sourceLineNo">499</span>            tx.mutations.tailSet(Mutation.key(originalMinKey)).clear();<a name="line.499"></a>
<span class="sourceLineNo">500</span>        else<a name="line.500"></a>
<span class="sourceLineNo">501</span>            tx.mutations.subSet(Mutation.key(originalMinKey), Mutation.key(originalMaxKey)).clear();<a name="line.501"></a>
<span class="sourceLineNo">502</span><a name="line.502"></a>
<span class="sourceLineNo">503</span>        // Add write lock and new tx mutation<a name="line.503"></a>
<span class="sourceLineNo">504</span>        this.getLock(tx, minKey, maxKey, true);<a name="line.504"></a>
<span class="sourceLineNo">505</span>        tx.mutations.add(new Del(minKey, maxKey));<a name="line.505"></a>
<span class="sourceLineNo">506</span>    }<a name="line.506"></a>
<span class="sourceLineNo">507</span><a name="line.507"></a>
<span class="sourceLineNo">508</span>    synchronized void commit(SimpleKVTransaction tx) {<a name="line.508"></a>
<span class="sourceLineNo">509</span><a name="line.509"></a>
<span class="sourceLineNo">510</span>        // Prevent use after commit() or rollback() invoked<a name="line.510"></a>
<span class="sourceLineNo">511</span>        if (tx.stale)<a name="line.511"></a>
<span class="sourceLineNo">512</span>            throw new StaleTransactionException(tx);<a name="line.512"></a>
<span class="sourceLineNo">513</span>        tx.stale = true;<a name="line.513"></a>
<span class="sourceLineNo">514</span><a name="line.514"></a>
<span class="sourceLineNo">515</span>        // Release all locks<a name="line.515"></a>
<span class="sourceLineNo">516</span>        if (!this.lockManager.release(tx.lockOwner)) {<a name="line.516"></a>
<span class="sourceLineNo">517</span>            throw new TransactionTimeoutException(tx,<a name="line.517"></a>
<span class="sourceLineNo">518</span>              "transaction taking too long: hold timeout of " + this.lockManager.getHoldTimeout() + "ms has expired");<a name="line.518"></a>
<span class="sourceLineNo">519</span>        }<a name="line.519"></a>
<span class="sourceLineNo">520</span><a name="line.520"></a>
<span class="sourceLineNo">521</span>        // Check subclass state<a name="line.521"></a>
<span class="sourceLineNo">522</span>        this.checkState(tx);<a name="line.522"></a>
<span class="sourceLineNo">523</span><a name="line.523"></a>
<span class="sourceLineNo">524</span>        // If there are no mutations, there's no need to write anything<a name="line.524"></a>
<span class="sourceLineNo">525</span>        if (tx.mutations.isEmpty())<a name="line.525"></a>
<span class="sourceLineNo">526</span>            return;<a name="line.526"></a>
<span class="sourceLineNo">527</span><a name="line.527"></a>
<span class="sourceLineNo">528</span>        // Commit mutations<a name="line.528"></a>
<span class="sourceLineNo">529</span>        this.preCommit(tx);<a name="line.529"></a>
<span class="sourceLineNo">530</span>        boolean successful = false;<a name="line.530"></a>
<span class="sourceLineNo">531</span>        try {<a name="line.531"></a>
<span class="sourceLineNo">532</span>            for (Mutation mutation : tx.mutations)<a name="line.532"></a>
<span class="sourceLineNo">533</span>                mutation.apply(this.kv);<a name="line.533"></a>
<span class="sourceLineNo">534</span>            successful = true;<a name="line.534"></a>
<span class="sourceLineNo">535</span>        } finally {<a name="line.535"></a>
<span class="sourceLineNo">536</span>            tx.mutations.clear();<a name="line.536"></a>
<span class="sourceLineNo">537</span>            this.postCommit(tx, successful);<a name="line.537"></a>
<span class="sourceLineNo">538</span>        }<a name="line.538"></a>
<span class="sourceLineNo">539</span>    }<a name="line.539"></a>
<span class="sourceLineNo">540</span><a name="line.540"></a>
<span class="sourceLineNo">541</span>    synchronized void rollback(SimpleKVTransaction tx) {<a name="line.541"></a>
<span class="sourceLineNo">542</span><a name="line.542"></a>
<span class="sourceLineNo">543</span>        // Prevent use after commit() or rollback() invoked<a name="line.543"></a>
<span class="sourceLineNo">544</span>        if (tx.stale)<a name="line.544"></a>
<span class="sourceLineNo">545</span>            return;<a name="line.545"></a>
<span class="sourceLineNo">546</span>        tx.stale = true;<a name="line.546"></a>
<span class="sourceLineNo">547</span><a name="line.547"></a>
<span class="sourceLineNo">548</span>        // Release all locks<a name="line.548"></a>
<span class="sourceLineNo">549</span>        this.lockManager.release(tx.lockOwner);<a name="line.549"></a>
<span class="sourceLineNo">550</span>    }<a name="line.550"></a>
<span class="sourceLineNo">551</span><a name="line.551"></a>
<span class="sourceLineNo">552</span>// Internal methods<a name="line.552"></a>
<span class="sourceLineNo">553</span><a name="line.553"></a>
<span class="sourceLineNo">554</span>    private /*synchronized*/ void getLock(SimpleKVTransaction tx, byte[] minKey, byte[] maxKey, boolean write) {<a name="line.554"></a>
<span class="sourceLineNo">555</span><a name="line.555"></a>
<span class="sourceLineNo">556</span>        // Attempt to get the lock<a name="line.556"></a>
<span class="sourceLineNo">557</span>        LockManager.LockResult lockResult;<a name="line.557"></a>
<span class="sourceLineNo">558</span>        try {<a name="line.558"></a>
<span class="sourceLineNo">559</span>            lockResult = this.lockManager.lock(tx.lockOwner, minKey, maxKey, write, tx.waitTimeout);<a name="line.559"></a>
<span class="sourceLineNo">560</span>        } catch (InterruptedException e) {<a name="line.560"></a>
<span class="sourceLineNo">561</span>            this.rollback(tx);<a name="line.561"></a>
<span class="sourceLineNo">562</span>            Thread.currentThread().interrupt();<a name="line.562"></a>
<span class="sourceLineNo">563</span>            throw new RetryTransactionException(tx, "transaction interrupted while waiting to acquire lock", e);<a name="line.563"></a>
<span class="sourceLineNo">564</span>        }<a name="line.564"></a>
<span class="sourceLineNo">565</span><a name="line.565"></a>
<span class="sourceLineNo">566</span>        // Check result<a name="line.566"></a>
<span class="sourceLineNo">567</span>        switch (lockResult) {<a name="line.567"></a>
<span class="sourceLineNo">568</span>        case SUCCESS:<a name="line.568"></a>
<span class="sourceLineNo">569</span>            break;<a name="line.569"></a>
<span class="sourceLineNo">570</span>        case WAIT_TIMEOUT_EXPIRED:<a name="line.570"></a>
<span class="sourceLineNo">571</span>            this.rollback(tx);<a name="line.571"></a>
<span class="sourceLineNo">572</span>            throw new RetryTransactionException(tx, "could not acquire lock after " + tx.waitTimeout + "ms");<a name="line.572"></a>
<span class="sourceLineNo">573</span>        case HOLD_TIMEOUT_EXPIRED:<a name="line.573"></a>
<span class="sourceLineNo">574</span>            this.rollback(tx);<a name="line.574"></a>
<span class="sourceLineNo">575</span>            throw new TransactionTimeoutException(tx,<a name="line.575"></a>
<span class="sourceLineNo">576</span>              "transaction taking too long: hold timeout of " + this.lockManager.getHoldTimeout() + "ms has expired");<a name="line.576"></a>
<span class="sourceLineNo">577</span>        default:<a name="line.577"></a>
<span class="sourceLineNo">578</span>            throw new RuntimeException("internal error");<a name="line.578"></a>
<span class="sourceLineNo">579</span>        }<a name="line.579"></a>
<span class="sourceLineNo">580</span>    }<a name="line.580"></a>
<span class="sourceLineNo">581</span>}<a name="line.581"></a>
<span class="sourceLineNo">582</span><a name="line.582"></a>




























































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